Candles made of conventional waxes are well known. A major decorative drawback to such a candle is that the use of waxes necessitates that the candle be opaque, thus limiting the ornamental capacity of the candle with respect to embedded decorative features.
Clear oil jar candles are also known in the art. However, prior to the present invention, these candles have been in liquid form only. These clear liquid candles, while permitting a type of embedded ornamental feature, do not permit the shaping of, for example, a pillar candle. These liquid candles are known to accumulate dust and other particulate matter from the air, thereby requiring that the oil be periodically discarded for aesthetic reasons. Additionally, liquid oil candles may spill and damage furnishings and the like. As yet another drawback, liquid candles must be assembled by the user.
U.S. Pat. No. 5,395,233 discloses a process for producing a potpourri wax candle. While such a candle has a decorative feature embedded therein, it is of a complex layered structure, and thus not easily manufactured.
U.S. Pat. No. 5,132,355 discloses a polyethylene block copolymer gelling agent, which may be used as a base for a decorative molded candle. This candle, however, is not transparent, and thus is of limited decorative value.
The present invention overcomes the problems in the prior art by providing stiff gel candles that are transparent. Thus, the candles of the invention permit the decorative shaping advantages of conventional wax candles as well as the embedded ornamental advantages of liquid oil candles. The candle of the present invention therefore provides an improved substitute for the conventional wax pillar or jar candle and for liquid oil jar candles.
The present invention involves a new use for oil-containing block copolymer gels as the hydrocarbon source of a candle. There is a need in the art for candles with improved aesthetic properties. Stiff transparent candles, into which decorative features have been added, are particularly desired. Accordingly, in this invention, advantageous combinations of block copolymers and oils are provided which produce heterophase thermally reversible mineral oil gels, and which have desirable properties for application as a clear, stiff gel candle.
The current methodology for producing mineral oil containing gels includes the use of metal soaps, surfactants (microemulsions), homopolymers, ionic homo- and copolymers and block copolymers. Some common gelling agents are fatty acid soaps of lithium, calcium, sodium, aluminum, zinc and barium. A number of homo- and copolymers have been used to gel hydrocarbon systems at certain polymer treatment levels including atactic ethylene-propylene. Homopolymers or copolymers which have pendant salt groups also form ion rich aggregates in a non-polar matrix. The ionic interaction and resultant polymer properties of these compositions, however, are dependent on the type of polymer backbone, type of ionic moiety and type of cation. Sulfonated polystyrenes exemplify this kind of system. Surfactant combinations have also been used to gel mineral oil/water systems. Surfactants are used at about 30 weight percent to gel oil and to gel 1:4 oil and water mixtures. Nonionic surfactants such as polyoxyethylene sorbitan monooleates exemplify these type of systems.
Block copolymers are also known to provide physical cross-links to gels by selective sulfonation and subsequent phase separation of a particular block. Block systems including styrene-isoprene, styrene-butadiene and styrene ethylene oxide copolymers have been used for this cross-linking.
The advantages of the candle of the invention, which are set forth below or easily recognized by those of ordinary skill in the art, are provided by use of firm heterophase, thermally reversible mineral oil gels as the hydrocarbon portion of the candle.